The effects of in-process cooling during friction stir welding of 7475 aluminium alloy

• Main Authors: Jacob, Ashish, Maheshwari, Sachin, Siddiquee, Arshad Noor, Al-Ahmari, Abdulrahman, Abidi, Mustufa Haider, Konovalov, Sergey, Chen, Xizhang
• Format: Article
• Language: English
• Published: Penerbit Universiti Kebangsaan Malaysia 2021
• Online Access: http://journalarticle.ukm.my/18069/1/20.pdf; http://journalarticle.ukm.my/18069/; https://www.ukm.my/jsm/malay_journals/jilid50bil9_2021/KandunganJilid50Bil9_2021.html

Certain age hardenable alloys such as AA7475 cannot be joined with perfection using fusion welding techniques. This requires non-conventional welding technique such as friction stir welding process to join these ‘difficult to weld’ alloys. In this study, three different cooling conditions i.e. cryogenic, sub-zero, and zero-degree Celsius temperature conditions have been analyzed to understand its impact on the welding process. In-process cooling was found to behave effectively and also enhanced the mechanical properties of the welded joints. A stable microstructure was clearly seen in the images observed under the metallurgical microscope. The weld efficiencies were found to be good in each of the samples which are indicative of a strong metallic joint. The effective cooling conditions employed had an overall positive impact on the joint.